Carbonic Anhydrase IV Isoenzyme (CA IV)

Carbonic anhydrase IV (CA IV) is a membrane-associated isozyme of the carbonic anhydrase family that catalyzes the reversible hydration of carbon dioxide. It is anchored to the plasma membrane via a glycosylphosphatidylinositol (GPI) anchor. CA IV is expressed predominantly on the luminal surfaces of pulmonary capillaries, proximal renal tubules, and capillary endothelial cells in various tissues. It facilitates gas exchange in the lungs and acid-base balance in the kidneys. Mutations in CA IV are linked to retinitis pigmentosa type 17 (RP17), and inhibitors like acetazolamide and brinzolamide are used therapeutically, particularly in glaucoma treatment.

Other names

Carbonic anhydrase 4CA4

Sulfonamides (e.g., acetazolamide, brinzolamide) bind directly within the active site, inhibiting the enzyme's catalytic activity.